The present invention relates to image processing, and more particularly, to a method of displaying luminance of a subject and a digital photographing apparatus using the method.
Digital photographing apparatuses such as digital cameras include a liquid crystal display (LCD) as a display unit and a user can view photographed images or images recorded in a memory card by displaying the images on the LCD. Moreover, by pushing a certain button such as a histogram button, a histogram showing luminance distribution of the subject can be displayed. The user can select exposure correction with reference to the histogram displayed on the LCD and photograph images with rich gradation even when the user is not skilled at manipulation of the digital camera.
FIGS. 1A and 1B are diagrams for explaining a conventional method of displaying luminance histograms of a subject. Referring to FIGS. 1A and 1B, in the conventional art, a histogram is displayed to display luminance information of a whole image. That is, the histogram displays the number of pixels of luminance corresponding to the whole image. Also, as illustrated in FIG. 1B, DSLR or high quality digital cameras display luminance histograms of R/G/B pixels, respectively.
Conventional histograms or RGB histograms display the screen luminance of the whole image, and thus luminance of regions or positions of the image need to be detected intuitively by the human's eyes. Also, since the luminance of the whole image is displayed using histograms, even if the background, which is not of concern to the user, is bright, and people, which are of interest to the user, are photographed dark, the total histogram of the image may be marked as being in a proper range.